Surface functionalization introduces chemical functional groups to a surface. This way, functional materials can be designed from substrates with standard bulk material properties. Prominent examples can be found in semiconductor industry and biomaterial research. In both cases, plasma processing technologies were successfully employed.
In chemistry, theoretical yield is calculated assuming that there is only one reaction involved, all of the reactant is converted into product and all the product is collected. It is the theoretical result of a chemical reaction.
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Third phase is the term for a stable emulsion which forms in a solvent extraction system when the original two phases (aqueous and organic) are mixed.
One term for the thrid phase found in PUREX plants is crud (Chalk River Unknown Deposit). One common crud is formed by the reaction of zirconium salts (from fission) with degraded tributyl phosphate (TBP). The TBP degrades into dibutyl hydrogen phosphate and then into butyl dihydrogen phosphate. The dibutyl hydrogen phosphate and the zirconium can form polymeric solid which is very insoluble.
Tritiated water is a form of water where the usual hydrogen atoms are replaced with tritium. It is also called tritium oxide, or T2O or 3H2O. It is radioactive, and used to make self-illuminating devices called trasers. It is also used as a tracer for water transport studies in life-science research. Furthermore, since it naturally occurs in minute quantities, it can be used to acurately determine the age of various water-based liquids, such as vintage wines.
It should not be confused with heavy water.
The handling of this chemical may incur notable safety precautions. It is highly recommend that you seek the Material Safety Datasheet (MSDS) for this chemical from a reliable source such as SIRI, and follow its directions.
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Trypsin inhibitors are chemicals that reduce the bio-availability of trypsin, an amino acid essential to nutrition of many animals, including humans.
There are four commercial sources of trypsin inhibitors.
| Source | Molecular weight | Inhibitatory power |
| Lima Beans | 8-10 kDa | 2.2 times weight |
| Bovine Pancreas | 6.5 kDa | 2.5 times weight |
| Ovomucoid | 8-10 kDa | 1.2 times weight |
| Soybeans | 20.7-22.3 kDa | 1.2 times weight |
There are six different lima bean inhibitors.
Ovomucoids are the glycoprotein protease inhibitors found in avian egg white. There are other protease inhibitors in ovomucoids as well.
Kunitz inhibitor is the best known pancreatic inhibitor. Chymotryptin is also inhibited by this chemical, but less tightly. When extracted from lung tissue, this is known as aprotinin.
Soybeans contain several inhibitors; the one in the chart is considered the primary one. All of them bind chymotryptin to a lesser degree.
Unsolved problems in chemistry tend to be (”can we make X compound”) and are solved rather quickly, but here are some persistent questions with deep implications:
Vanish toilet bowl cleaner is manufactured by S. C. Johnson & Son.
They obtained the brand through the purchase of The Drackett Company in 1992. Drackett purchased the product from inventor Judson Dunaway.
Judson Dunaway Corporation of Dover NH introduced Vanish in 1937 as a competitor to Sani-Flush, a toilet bowl cleaner made since 1911. The products were substantially the same; the last Sani-Flush patent had expired in 1932.
In 1947, Hygenic Products sued Judson Dunaway on grounds of trademark infringement and unfair competition. Sani-Flush used a yellow 22-ounce can showing a woman pouring bowl cleaner into a toilet. Initially, Vanish sold their product in a white 22-ounce showing the bowl cleaner coming from the bottom of the “I”. After WWII, Vanish advertising started to show a woman pouring the product into a toilet bowl, and then a hand, obviously female, pouring powder into a toilet bowl. Dunaway won on appeal.
The active ingredient in crystal bowl cleaners is sodium bisulfite (also known as sodium hydrogen sulfite). Various surfactants are added. This forms an acid when mixed with water. Most other household cleaners are basic (alkaline) in nature.
Sources:
Windex’s flagship product
Windex is a trademark for a glass and light-duty hard surface cleaner made since 1992 by S. C. Johnson & Son and popular in the United States and Canada since the mid-20th century. It is marketed as Windolene in the United Kingdom.
The popularity of Windex in the US has led to the generic use of the trademark for any similar product, including those marketed under different brands, or simply labelled, e.g., Window Cleaner.
Windex-like products typically contain detergents, ammonia, fragrance to moderate the odor of ammonia, and some form of dye. The original modern Windex was colored a light, transparent shade of blue, but varieties are marketed today in a variety of colors and fragrances, touting additives such as vinegar or lemon juice.
When Windex was first invented in 1933 by Harry R. Drackett, it was essentially 100% solvent, and as a flammable product, it had to be sold in metal cans. When modern surfactants were introduced after WWII, the product was reformulated.
The Sam Wise patent #3,463,735 lists several example formulae, one of which is 4.0% isopropyl alcohol (a highly volatile solvent) 1% ethylene glycol monobutyl ether (a less volatile solvent), 0.1% Sodium laurel sulfate (a surfactant), 0.01 tetrasodium pyrophosphate (a water softener), 0.05% of 28% Ammonia (added more for smell than for cleaning ability), 1% of a dye solution, and 0.01% perfume. This formula was not only significantly less expensive to manufacture, but allowed the product to be packaged in glass bottles and dispensed with a plastic sprayer.
The product was recently reformulated [1] to more environmentally-desirable solvents. Reducing solvent levels paradoxically results in cleaner glass because the glass cleaner does not evaporate as quickly, and the consumer must polish the glass longer.
The blue color has inspired bartenders to name similarly tinted mixed drinks after it. Blue Curaçao is a common ingredient; for instance, a “Windex shot” typically contains vodka, triple sec, and blue Curaçao for color.
In the comedy film My Big Fat Greek Wedding, Windex was presented as a placebo or folk remedy for external use against most non-disabling ailments. (This parallels an actual folk belief in similar use of the WD-40 brand of penetrating oil.)
Sources: “Philip W. Drackett: Earned profits, plaudits” By Barry M. Horstman, Cincinnati Post, May 21, 1999.
The Gold Book or Compendium of Chemical Terminology (ISBN 0865426848) is a book published by IUPAC containing internationally accepted definitions for terms in chemistry.
Work on the first edition was initiated by Victor Gold, hence the name. The first edition was published in 1987 and the second one, edited by A. D. McNaught and A. Wilkinson, was published in 1997. A slightly expanded version of the Gold Book is also freely searchable online.
In chemistry, analogs or analogues are compounds in which one or more individual atoms have been replaced, either with a different atom, or with a different functional group. Pharmaceuticals are one area in which a ‘lead compound’ found to have activity is elaborated by creating a family of analogs.
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